Pipe wrench



E. H. BOOTH.

PIPE WRENCH.

APPLICATION FILED OCT 2!.1921.

1,41 1,471. Patented p -4,1922.

UNITED STATES PATENT OFFICE.

rirn wannon.

Specification of Letters Patent. Patented Apr. 4,1922.

Application filed October 21, 1921. Serial No, 509,349.

1 0 all whom it may co-ncemi:

Be it known that I, EnnNnzn-n H. Boo'rr-r, a citizen of the United States, resident of Binghamton, in'the county 01 Broome and State of New York, have made a certain new and useful Invention in Pipe renches; and I declare the following to be a full, clear, and exact description of the same, such as will enable others skilled in the art to which it appertains to make and use the invention, reference being had to the accompanying drawings, and to letters or figures of reference marked thereon, which form a part of this specification.

Figure 1 is a side view of the wrench partly broken away.

Figure 2 is a similar view with the movable jaw rocked to engage the work.

Figure 3 is a similar view with the handle or clamp lever released.

Figure 4-. is a section on the line l--'-'t, Figure 3.

The invention has relation to wrenches, and particularly to pipe wrenches, having for an object to provide an improved wrench of light weight and reliable nature, capable of quick adjustment and of holding the adjustment without change by rough usage, and capable of economical manufacture. Other objects and advantages will appear.

a The invention consists in the novel con struction and combinations of parts as hereinafter set forth.

In the accompanying drawings illustrating an embodiment of the invention, the numeral 1 designates the stationary jaw, having a. shank or handle bar 2, provided with opposite extensions or check lugs 3, 3, between which is located the shank 1 of the movable j aw 5, the shanks of the two jaws being located in substantially parallel relation as is common in pipe wrenches or wrenches of this type. i I

The shank of the movable jaw is provided with a longitudinal series of teeth 6, forming a rack, and having engagement with the teeth 7 of a shorter rack 8, of arouate nature, located upon the shank ofthe rigid jaw, between the lugs 3, 3.

A short handle lever 9 is fulcrumed upon a pin 10, connecting the outer ends of the lugs 3, 3, thereby confining the shank of the movable jaw against movement in the plane of the shank of the rigid jaw, the lugs 3. 3. confining said shank against movement at right angles to the plane of the rigid jaw shank, the said shank being therefore permitted onlya movement in a longi tudinal direction to open or close the two jaws.

These cheek lugs 3, 3, are preferably provided through the medium of a yoke piece 3, which fits upon the shank of the rigid jaw, being secured thereto by the pins or bolts 3 and the branches or checks of which embrace the shank of the movable jaw and thepivotal end of the lever 9.

When the handle lever 9 is released and in the position shown in Figure 3 of the drawings, the movable jaw shank is per- 'mitted a movement away from the stationary jaw shank to disengage the teeth of the two racks, the former shank being then freely adjustable longitudinally to the desired degree, after which the handle is operated to the positionshown in Figure 3 in dotted lines, wherein the cam or eccentric spring 11 of the head 11 of said lever acts to force the movable jaw sha-nk'towards the rigid jaw shank'u'nti'l the engagementof the teeth of the two racks is effected.

When the leverOis released, the eccentric spring 11 through inherent elasticitytakes an outward position away fromthe lever head, and a sufiicient interval is provided between the lever'head and the arcuate rack to admit of the free longitudinal adjustment of the movable jaw shank to open or close the jaws. As the handle lever is operated. to press the movable jaw shank towards the fixed jaw shank, the eccentric spring will be-gradually pressed towards the lever upon which it-is mounted, and when the point of greatest eccentricity of the spring passes out of contact with the movable jaw shank, the elasticity of the spring will cause the handle lever to snap to fully closed position whereinthe spring is pressed snugly against the lever thereby avoiding slippage of the engaged teeth. The free end of the eccentric spring bears at 12 against the head of the lever to thereby stifi'en the spring.

When the wrench is applied to the pipe.

the oppositely inclined teeth 13 and 14 of the rigid and movable jaws, will rock the movable jaw upon the center tooth of the arcuate rack as a center to automatically close the jaws to the work, this gripping action becoming stronger with added power applied to the wrench. In the rocking movement of the movable jaw, the tooth or teeth at one side of the center tooth of the arcuate'rack are engaged with the teeth of the movable jaw shank whereby the strain upon the teeth is distributed and the two racks are always securely engaged with each other, the rock ng movement of the movable jaw being limited in this direction by engagement of the shank of the movable jaw with the jaw end of the shank of the rigid jaw at 15, as shown in Figure 2. The

embrace the shank of the rigid jaw, and

avoid any tendency of the parts from getting out of parallel relation. The said end of the movable jaw shankis also provided with a plate spring 17 engaging the shank of the rigid jaw, and assisting in maintaining' the parallel relation of the shanks'of the ri id and movable jaws.

he teeth 6 have an inclination or set towards the jaw end of the shank 4, to strengthen the teeth and enable them to better resist the strain upon saidshank tending to open the jaws in engaging the wrench with the work. The teeth 7 of the arcuate rack 8 are inclined or set in the opposite di rection for the same reason.

I claim f 1. In a pipe wrench, a rigid jaw having a handle shank, the latter having an arcuate toothed rack, a yoke piece rigidly secured to said shank and having opposite cheek lugs, a movable jaw having a shank located and slidable between said lugs and provided with a rack the teeth of which engage the teeth of said arcuate rack, and yieldable means mounted at the outer ends of said lugs and engaging the shank of the movable jaw to maintainthe engagement of the rack teeth, the movable jaw being rockable upon the arcuate rack to automatically close the jaws to the work.

2. In a pipe Wrench, a rigid jaw having a handle shank, the latter having an arcuate toothed rack, a yoke piece secured to said shank and having opposite cheek lugs, a

movable jaw having a shank located and slidable between said lugs and provlded with a rack the teeth of which engage the teeth of said arcuate rack, the rigid and movable j aws having teeth oppositely set or inclined,

a pin connecting the outer ends of said lugs, and a handle lever mounted upon said pm and normally maintaining the engagement of the rack teeth, the movable jaw being rockable upon the teeth of the arcuate me to automatically close the jaws to the work. 3. In a pipe wrench, a rigid jaw having a handle shank, the latter having an arcuate toothed rack, a yoke piece secured to said shank and having opposite cheek lugs, a movable jaw having a shank located and slidable between said lugs and provided with a rack the teeth of which enga e the teeth of said arcuate rack, the rigid and movable jaws havingteeth oppositely set or inclined, a pin connecting the outer ends of said lugs, and a handle lever mounted upon said pin and having an eccentric spring acting to normally press the movable jaw H towards the rigid jaw and maintain the engagement of the teeth of the two racks, the movable jaw being rockable upon the teeth of the arcuaterack to automatically close the jaws tothe work; a a

4. In a pipe wrench, a rigid jaw having a handle shank, the latter having an arcuate toothed rack, a yoke piece secured to said shank and having opposite cheek lugs, a

movable jaw having a shank located and slidable between said lugs and provided with a rack, the teeth of which engage the teeth oi? said arcuate rack, the rigid and movable jaws having teeth oppositely set or inclined,

a pin connecting the outer ends of said lugs, 

